Compact composite handrails with enhanced mechanical properties

ABSTRACT

A handrail includes a carcass, a stretch inhibitor arranged within the carcass, a cover bonded to the carcass, and a sliding layer secured to the carcass. At a central width axis of the handrail, a face height between an upper exterior surface of the cover and a bottom surface of the sliding layer may be less than about 8.0 mm. The carcass may be formed of a first thermoplastic material, the cover may be formed of a second thermoplastic material, and the first thermoplastic material may be harder than the second thermoplastic material. The first thermoplastic material may have a modulus at 100% elongation of between 10 and 16 MPa, and may have a hardness of between 93 and 96 Shore A.

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a continuation of U.S. application Ser. No. 15/570,012 filed onOct. 27, 2018, which is a national stage application of InternationalApplication No. PCT/2016/050522 filed on May 6, 2016, which claimspriority to U.S. Provisional Application No. 62/158,348 filed on May 7,2015, and the entire contents of each are hereby incorporated herein byreference.

FIELD

The present disclosure relates generally to handrails suitable for usewith an escalator, a moving walkway and/or other transportationapparatus.

BACKGROUND

The following paragraphs are not an admission that anything discussed inthem is prior art or part of the knowledge of persons skilled in theart.

International Publication No. WO/2000/001607 discloses a moving handrailconstruction, for escalators, moving walkways and other transportationapparatus with a handrail having a generally C-shaped cross section anddefining an internal generally T-shaped slot. The handrail is formed byextrusion and comprises a first layer of thermoplastic materialextending around the T-shaped slot. A second layer of thermoplasticmaterial extends around the outside of the first layer and defines theexterior profile of the handrail. A slider layer lines the T-shaped slotand is bonded to the first layer. A stretch inhibitor extends within thefirst layer. The first layer is formed from a harder thermoplastic thanthe second layer, and this has been found to give improved properties tothe lip and improved drive characteristics on linear drives.

International Publication No. WO/2009/033270 discloses a method andapparatus for extrusion of an article. A die assembly can apply flows ofthermoplastic material to an array of reinforcing cables to form acomposite extrusion. A slider fabric can be bonded to one side of thecomposite extrusion. After exiting the die assembly, the slider fabriccan act to support the extrudate as it passes along an elongate mandrel,which can cause the base of the slider fabric to change shape from aflat profile to the final internal profile of the article. The extrudedarticle can then be cooled to solidify the material. The die can includecooling for the slider fabric and means for promoting penetration of thethermoplastic into reinforcing cables.

International Publication No. WO/2009/033272 discloses modifiedhandrails for use in escalators, moving walkways and othertransportation apparatus. Handrail can include a configuration for acable array as a stretch inhibitor that reduces cable buckling undersevere flexing conditions. Handrail can also include a configuration forfirst and second thermoplastic layers in the lip portions that reducesstrain and bending stresses and increases fatigue failure life undercyclic loading conditions. Handrail can also include, for the stretchinhibitor, the use of cables comprising large outer strands and smallinner strands that enable penetration and adhesion within the firstlayer and can reduce incidence of fretting or corrosion.

International Publication No. WO/2009/033273 discloses a method andapparatus for pretreatment of slider layer for extruded handrails havinga slider layer source, a means of conveying the slider layer to aheating module which subjects the slider layer to an elevatedtemperature for a residence time, and a means of conveying the sliderlayer to an extrusion die head. One or more control feeders may beimplemented for maintaining portions of the slider layer in asubstantially tension-free loop as the slider layer is conveyed from theslider layer source to the extrusion die head. A cooling zone may beincluded to ensure adequate cooling between the heating module and theextrusion die head. Means for reducing heat transfer between theextrusion die head and the slider layer is also provided.

The entire contents of International Publication Nos. WO/2000/001607,WO/2009/033270, WO/2009/033272 and WO/2009/033273 are herebyincorporated herein by reference.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings included herewith are for illustrating various examples ofapparatuses and methods of the present disclosure and are not intendedto limit the scope of what is taught in any way. In the drawings:

FIG. 1 is a sectional view of an example of a handrail;

FIG. 2 is a further sectional view of the handrail;

FIG. 3 is a schematic view of a test arrangement for lip stiffness ofthe handrail;

FIG. 4 is a schematic view of a test arrangement for straightness of thehandrail;

FIG. 5 is a sectional view of FIG. 4;

FIG. 6 is a schematic view of the handrail being reverse bend wound;

FIG. 7 is a sectional view of another example of a handrail;

FIG. 8 is a sectional view of an example of an intermediate handrailproduct;

FIG. 9 is a further sectional view of the intermediate handrail product;and

FIG. 10 is a perspective view of part of a mandrel for forming thehandrail from the intermediate handrail product.

DETAILED DESCRIPTION

Various apparatuses or methods will be described below to provide anexample of an embodiment of each claimed invention. No embodimentdescribed below limits any claimed invention and any claimed inventionmay cover apparatuses and methods that differ from those describedbelow. The claimed inventions are not limited to apparatuses and methodshaving all of the features of any one apparatus or method describedbelow, or to features common to multiple or all of the apparatuses ormethods described below. It is possible that an apparatus or methoddescribed below is not an embodiment of any claimed invention. Anyinvention disclosed in an apparatus or method described below that isnot claimed in this document may be the subject matter of anotherprotective instrument, for example, a continuing patent application, andthe applicant(s), inventor(s) and/or owner(s) do not intend to abandon,disclaim or dedicate to the public any such invention by its disclosurein this document.

Referring to FIG. 1, a handrail is shown generally at reference numeral10. The handrail 10 includes a carcass 12, a stretch inhibitor 14, acover 16, and a sliding layer 18.

In the example illustrated, the carcass 12 includes a first side carcassportion 20, a second side carcass portion 22 spaced apart from the firstside carcass portion 20, and a central carcass portion 24 of generallyuniform thickness extending between the first and second side carcassportions 20, 22. The stretch inhibitor 14 is shown arranged within thecentral carcass portion 24. The carcass 12 is shown tapering inthickness around the first and second side carcass portions 20, 22. Thecentral carcass portion 24 delineates an upper interior surface 26. Thefirst and second side carcass portions 20, 22 delineate first and secondconcave interior surfaces 28, 30, respectively. The first and secondconcave interior surfaces 28, 30 adjoin the upper interior surface 26 oneither side thereof.

In the example illustrated, the cover 16 is bonded directly to thecarcass 12 at an interface to form a continuous body. The cover 16includes a first side cover portion 32 covering the first side carcassportion 20, a second side cover portion 34 covering the second sidecarcass portion 22, and a central cover portion 36 of generally uniformthickness extending between the first and second side cover portions 32,34, adjacent to the central carcass portion 24. The central coverportion 36 delineates an upper exterior surface 78. The upper exteriorsurface 78 may exhibit a minor convex curve, as illustrated.

In the example illustrated, the first and second side cover portions 32,34 delineate first and second convex exterior surfaces 38, 40,respectively. The first and second convex exterior surfaces 38, 40adjoin the top exterior surface 78 on either side thereof.

In the example illustrated, the first and second side cover portions 32,34 further delineate generally opposed first and second side interiorsurfaces 42, 44, respectively. The first and second side cover portions32, 34 may each have increasing thickness towards the first and secondside interior surfaces 42, 44, respectively, which compensates for thetapering of the carcass 12.

In the example illustrated, the first and second side cover portions 32,34 yet further delineate first and second lower interior surfaces 46,48. The first lower interior surface 46 is shown adjoined between thefirst concave interior surface 28 and the first side interior surface42, and the second lower interior surface 48 is shown adjoined betweenthe second concave interior surface 30 and the second side interiorsurface 44, respectively.

In the example illustrated, the sliding layer 18 is secured to the upperinterior surface 26, the first and second concave interior surfaces 28,30, the first and second lower interior surfaces 46, 48, and the firstand second side interior surfaces 42, 44. The sliding layer 18 mayinclude curved ends that are embedded within the cover 16 adjacent tothe first and second side interior surfaces 42, 44, as illustrated.

Various dimensions of the handrail 10 are illustrated in FIG. 2. In theexample illustrated, the handrail 10 has a face height 52 and a sidewidth 54. The face height 52 is a vertical dimension at a central widthaxis 56 of the handrail 10 between a bottom surface 58 of the slidinglayer 18 and the upper exterior surface 78 (the surfaces 58, 78 areshown in FIG. 1). The side width 54 is a horizontal dimension at acentral height axis 50 of the handrail 10 between an inner side surface60 of the sliding layer 18 and the second convex exterior surface 40(the surfaces 60, 40 are shown in FIG. 1). The handrail 10 may begenerally symmetrical about the central width axis 56, as illustrated,and therefore the side width may be the same on either side of thehandrail 10.

The present disclosure is directed to handrails that are generallycompact in size. In some examples, the face height 52 may be less thanabout 8.0 mm, and the side width 54 may be less than about 7.5 mm. Insome examples, the face height 52 may be less than about 7.5 mm, and theside width 54 may be less than about 7.0 mm. In some examples, the faceheight 52 may be between 7.0 and 7.5 mm, and the side width 54 may bebetween 6.5 and 7.0 mm. The carcass 12 may constitute at least 60% ofthe face height 52 or the side width 54 dimensions of the handrail 10,as illustrated.

Vertical dimensions of the handrail 10 further include a handrail height62, a slot height 64, and a lip height 66. Horizontal dimensions of thehandrail 10 further include a handrail width 68, a slot width 70, amouth width 72, and a stretch inhibitor width 74.

Referring to FIGS. 1 and 2, the stretch inhibitor 14 is shown formed ofa plurality of longitudinal cables 76 disposed along a central planewithin the central carcass portion 24. In the example illustrated, endones of the cables 76 are offset inwardly in relation to the first andsecond side interior surfaces 42, 44. In other words, the stretchinhibitor width 74 is substantially less than the mouth width 72. Inoperation, having the ones of the cables 76 spaced away from regions ofstress in the portions 20, 22, 32, 34 may affect the ability of thestretch inhibitor 14 to retain a neutral plane during flexing.

Dimensions for a particular example of the handrail 10 are provided inTable 1. These dimensions are intended to be illustrative butnon-limiting.

TABLE 1 Dimension Reference mm face height 52 7.0 side width 54 6.5handrail height 62 23.5 slot height 64 9.5 lip height 66 7.0 handrailwidth 68 72.0 slot width 70 59.0 mouth width 72 39.0 stretch inhibitorwidth 74 37.2

The compact construction of the handrail 10 may reduce the powerrequired to drive the handrail 10. For example, the handrail 10 may beapproximately 30 to 40% less weight than a traditional handrail productthat it is intended to replace. This reduction in weight will translateto lower power consumption on escalators, moving walkways and/or othertransportation apparatus.

Due to the compact sizing, the inventors have recognized thatappropriate materials selection for the components is required toachieve satisfactory mechanical properties of the handrail 10.

The carcass 12 may be formed of a first thermoplastic material, thecover 16 may be formed of a second thermoplastic material, and thesliding layer 18 may be formed of a fabric material. The firstthermoplastic material of the carcass 12 is generally stiffer and harderthan the second thermoplastic material of the cover 16, and serves toretain the mouth width 72 to provide a desired lip stiffness. Thecarcass 12 also serves to protect the stretch inhibitor 14, which inthis case is formed of the cables 76, and the bond between the cables 76and the first thermoplastic material of the carcass 12 may be improvedby adhesive (not shown).

For the carcass 12, polyester thermoplastic polyurethane may beimplemented as the first thermoplastic material. In some examples, thefirst thermoplastic material of the carcass 12 may have a modulus at100% elongation of between about 10 and 16 MPa and a hardness of betweenabout 93 and 96 Shore A. In some particular examples, the firstthermoplastic material of the carcass 12 may have a modulus of betweenabout 12 and 15 MPa at 100% elongation and a hardness of between 94 and95 Shore A. Exemplary specifications for the first thermoplasticmaterial of the carcass 12 are provided in Table 2, which are intendedto be illustrative but non-limiting.

TABLE 2 Property Specification Units Comments Formulation Polyester TPU— With anti- hydrolysis agent Hardness 93-96 Shore A ASTM D2240-00Tensile  40 (minimum) MPa ASTM D412 Strength Ultimate 400 (minimum) %ASTM D412 Elongation Modulus @ 100% 10-16 MPa ASTM D412 Elongation Glass−20 (maximum) ° C. By differential Transition scanning calorimetryProcessing Extrusion — — Melt Index  5-20 g 190° C./8700 g ASTM D1238

For the cover 16, polyester thermoplastic polyurethane may beimplemented as the second thermoplastic material. In some examples, thesecond thermoplastic material of the cover 16 may have a relatively lowmelt flow index, for example, on the order of between about 20 and 60 gunder the conditions listed in table 3. In some particular examples, thesecond thermoplastic material of the cover 16 may have a melt flow indexof between about 20 and 40 g under the conditions listed in table 3, anda broad molecular weight distribution so that a sharp melting point isavoided. Exemplary specifications for the second thermoplastic materialof the cover 16 are provided in Table 3, which are intended to beillustrative but non-limiting.

TABLE 3 Property Specification Units Comments Formulation Polyester TPU— With anti- hydrolysis agent Hardness 83-87 Shore A ASTM D2240-00Tensile  40 (minimum) MPa ASTM D412 Strength Ultimate 500 (minimum) %ASTM D412 Elongation Modulus @ 100% 4-6 MPa ASTM D412 Elongation Glass−20 (maximum) ° C. By differential Transition scanning calorimetryProcessing Extrusion — Broad molecular weight distribution Melt Index20-40 g 210° C./3800 g ASTM D1238

Exemplary specifications for the cables 76 of the stretch inhibitor 14are provided in Table 4, which are intended to be illustrative butnon-limiting.

TABLE 4 Property Specification Units Type High Tensile Steel — Cord,brass plated Construction Inner 3 × mm 0.20 ± 0.01 Outer 6 × 0.35 ± 0.01Twist 9.5 ± 0.5 mm S 1 turn per 18.0 ± 0.9 mm Z Linear 5.34 ± 0.27 g/mDensity Diameter 1.13 ± 0.06 mm (in) Strength 1870 (minimum) N

For the sliding layer 18, a woven spun polyester textile fabric may beused. In some examples, a three ply yarn may have residual shrinkage ofat least 7.0% under the conditions provided in table 6. In someexamples, the woven fabric may have a minimum warp shrinkage of at least8.75%. These high shrinkage values may be required so that the fabricshrinks and tightens in the process. Use of yarns and fabrics with lowershrinkage (generally referred to as “high tenacity”) may result in thetextile being stretched in the process and this stretch may be frozen orotherwise retained in the product after processing, thereby resulting ina higher modulus textile layer and a stiffer product. Exemplaryspecifications for the sliding layer 18 are provided in Tables 5, 6 and7, which are intended to be illustrative but non-limiting.

TABLE 5 STAPLE FIBERS Property Specification Units Test Method FiberType Polyester — — Staple Fiber 1.28 nominal Denier AATCC 20 LinearDensity Staple Length 38-52 mm ASTM D5103 Melting Point 255 ° C. ASTMD3418 (Peak - by DSC)

TABLE 6 YARN Property Specification Units Test Method Type SpunPolyester — — Yarn count 12 (50) Cotton ASTM D1907 Count (Tex)Anti-Static 22 Denier ASTM D1433 filament Yarn Twist 11.4 ± 0.8 TPI ASTMD1433 Yarn 4.5 (minimum) kg/end ASTM D2256 Strength Yarn 20 % ASTM D2256Elongation at Break Residual 7.0 (minimum) % ASTM 2259 Shrinkage(Method: Dry-Heat Exposure; 75 s at 200° C.) Number Yarns 3 (12/3construction) — — in Standard Ply Anti-Static 3 standard yarns — — Ply(standard ply) Construction blended with 1 anti- static filament PlyTwist 6.0 + 1/−0.5 TPI —

TABLE 7 WOVEN FABRIC Property Specification Units Test Method WeaveVenetian — — Anti-static 20% warp yarns — — plied yarn spacedapproximately addition every 5^(th) warp end level Width 1448 ± 13  mm —Roll Length 360 ± 10 m — Maximum 648 mm — O.D. of roll Warp Count 47 ± 1EPI — (Ends) Weft (fill) 44 ± 1 EPI — Count (Picks) Fabric 607 ± 34 g/m²— Weight Wide-Width 800 × 800 (minimum) N/cm — Tensile, Warp × WeftGauge  1.02 ± 0.08 mm — Crimp, Warp 20 ± 5 % — Crimp, Weft  5 ± 2 % —Warp 8.75 (minimum) % — Shrinkage Surface 1 × 10¹² (maximum) Ω/squareASTM D257 Resistivity

The sliding layer 18 may be prepared generally in accordance with thepretreatment methods and apparatuses disclosed in InternationalPublication No. WO/2009/033273. However, the inventors have developedthe following pretreatment and testing procedure for the handrail 10:

-   -   1. Using a knife, cut a sample piece of fabric from a bulk roll        to be tested. For example, the sample may have a length of 40 to        60 cm, and a width of no greater than 20 cm.    -   2. Using a pen, draw a plurality of lines of various lengths in        both warp and weft direction for measuring. For example, 4 to 6        lines of various lengths from 50 mm to 10 mm.    -   3. Using a set of calipers, measure the length of each of the        lines accurately to a tenth of a millimeter and record values.    -   4. Set two heated plates, arranged to provide heat to both sides        of the fabric, at a temperature of 200±3° C., and with a gap of        approximately 3 mm between the plates.    -   5. Insert the fabric between the plates in the gap for 75±1 s.    -   6. Let sample cool for approximately 2 m after removal from the        plates.    -   7. Using the calipers, measure each line again and record the        results.    -   8. Calculate shrinkage percentage for each measured line        according to equation (1).

$\begin{matrix}{{{Shrink}\mspace{14mu}{Percentage}} = {\frac{{{Initial}\mspace{14mu}{Length}} - {{Final}\mspace{14mu}{Length}}}{{Initial}\mspace{14mu}{Length}} \times 100\%}} & (1)\end{matrix}$

Exemplary results of the pretreatment and testing procedure are providedin Table 8.

TABLE 8 Sample Starting (mm) Shrunk (mm) % Change Width 138 125 9.42Warp #1 105.15 95.12 9.54 Warp #2 100.88 90.54 10.25 Warp #3 100.2888.61 11.64 Weft #1 100.99 91.3 9.60 Weft #2 103.05 93.06 9.69 Weft #3101.44 91.12 10.17 Avg Warp % Change 10.48 Avg Weft % Change 9.82

As noted in Table 7, shrinkage in the warp direction during thepretreatment should be at minimum 8.75% to yield a fabric that is bothflexible and strong. The inventors have found that if the fabric usedfor the sliding layer does not shrink in the warp direction by at least8.75% during pretreatment, the performance of the handrail 10 in dynamictesting may be compromised. Shrinkage in the weft direction has beenfound to be less important on the mechanical properties of the resultinghandrail 10.

The handrail 10 as disclosed herein may exhibit enhanced mechanicalproperties.

Lip stiffness refers to the force required to open the handrail lipapart using two mechanical jaws seated inside the handrail lip. This isone particular characteristic of the handrail 10 that may be important,as it is a safety consideration that relates to the ability of thehandrail to resist being pulled off of its guide. Referring to FIG. 3,to test lip stiffness, first and second jaw elements 80, 82 may bearranged to transfer load to a test piece of the handrail 10 on opposingsides of the axis 56. The first and second jaw elements 80, 82 may applythe load to the first and second side interior surfaces 42, 44 (FIG. 1).Each of the first and second jaw elements 80, 82 extend a length 84. Thelength 84 may be, for example, 30 mm, and the length of the test pieceshould substantially exceed the length 84 to avoid end effects. A lipstiffness value may be defined as the amount of force 86 necessary toincrease the mouth width 72 by a predetermined amount. In some examples,at least 10 kg is required to increase the mouth width 72 by 7 mm in anextruded section. In other examples, 7 kg may be required to increasethe mouth width 72 by 7 mm in a spliced section, in which a joint isformed between ends of two separate lengths of the handrail 10. Aspliced section may be lower strength due to it being heat treated, forexample, in accordance with the methods and apparatuses disclosed inInternational Publication No. WO 97/37834, the entire contents of whichare hereby incorporated herein by reference.

The handrail 10 may also be relatively good at maintaining straightnessalong its length under tension. Referring to FIGS. 4 and 5, the handrailis held between first and second supports 88, 90, and a tension force 92to its ends. A straightness value may be defined as a maximum deviation94 along a minimum length 96 of the handrail 10′ in tension. In someexamples, the handrail 10 may exhibit a maximum deviation 94 of 1 mm,along a minimum length 96 of 300 mm and a tension force 92 of 1000 N.

Another characteristic that may be measured is the force required forforward bending. A nominal force of 20 N may be required to bend an 800mm length of the handrail 10 90° over a jig with radius of 305 mm, witha maximum lip dimensional change while bent being +3/−1 mm. For backwardbending, a nominal force of 25 N may be required to bend a 1700 mmlength of the handrail 10 90° over a jig with radius of 610 mm, with amaximum lip dimensional change while bent being +3/−1 mm.

Furthermore, there is a permitted bending radii that allows the handrail10 to bend and flex with relatively smooth transitions. For a reverse(negative) bend, the handrail 10 may exhibit a 380 mm minimum bendingradii. For a forward (positive) bend, the handrail 10 may exhibit a 180mm minimum bending radii.

The handrail 10 may be manufactured generally in accordance with theextrusion methods and apparatuses disclosed in International PublicationNo. WO/2009/033270. However, after extruding and cooling the handrail10, it may be desirable store the handrail 10 in a reverse bendorientation. Referring to FIG. 6, a roller 98 may be used to invert theorientation of the handrail 10 and supply it to a reel 100. The reel 100should have a diameter that is sufficient to accommodate the permittedreverse bending radii of the handrail 10. The handrail 10 is wound aboutthe reel 100 to form a spool 102 of the handrail 10 maintained in areverse bend orientation. The reel 100 may then be stored ortransported.

Storing and aging the freshly extruded handrail 10 in this manner placesthe thermoplastic components furthest from the cables 76 and the neutralaxis and under slight tension. This is built in to the structure as thethermoplastic materials reach their final properties and shape whileaging on the reel for an extended period of time, for example, 48 hoursor more. In some examples, the handrail 10 in the reverse bendorientation may age on the reel for 7 days or more. This built in stressessentially makes the handrail 10 below the neutral axis longer so thatthe effects of thermoplastic and slider fabric shrinkage are negated tosome degree. If the handrail 10 is stored rolled in the forwarddirection, the handrail 10 may have a permanent forward set so that itmay be difficult to handle, more force may be required to bend it in thereverse direction, and it may be more prone to collapsing while bending.In contrast, when the handrail 10 is aged rolled in the reverseorientation, it may come off the reel and lay flat making handlingeasier, it may require less force to bend in reverse, and may be lessprone to kinking. This may be important with a compact product as thethinner cross section may be more prone to collapse and kinking.

Referring to FIG. 7, another handrail is shown generally at referencenumeral 110. For simplicity, similar components are given correspondingreference numerals as in FIG. 1 and the description is not repeated.Compared to the handrail 10, the carcass 112 of the handrail 110 tapersmore quickly in thickness around the first and second side carcassportions 120, 122, and therefore terminates further away from the firstand second side interior surfaces 142, 144. Due to the reduction of thefirst thermoplastic material in the carcass 112, and the resultantincrease in the second thermoplastic material in the cover 116, thehandrail 110 would exhibit lower lip stiffness compared to the handrail10.

Referring to FIG. 8, an intermediate handrail product is shown generallyat reference numeral 210. The intermediate handrail product 210 includesa carcass 212, a stretch inhibitor 214, a cover 216, and a sliding layer218. Materials for each of the components of the intermediate handrailproduct 210 may be similar to that described above for the handrail 10.

In the example illustrated, the sliding layer 218 includes a planarportion 220 and first and second upstanding edge portions 222, 224. Theupstanding edge portions 222, 224 are shown to have curved ends 226,228, respectively, that are embedded within the cover 216.

In the example illustrated, the carcass 212 is on the sliding layer 218and centrally disposed between the first and second upstanding edgeportions 222, 224. The carcass 212 is shown to be generally rectangular,and has rounded upper corners arranged between first and second edges230, 232 and a top surface of the carcass 212.

The cover 216 covers the carcass 212 and extends between the first andsecond upstanding edge portions 222, 224. In the example illustrated,the cover 216 contacts the carcass 212 at an interface to form acontinuous body. The cover 216 is shown to include first and secondbottom surfaces 234, 236, which are in contact with the planar portion220 of the sliding layer 218 between the upstanding edge portions 222,224 and the edges 230, 232 of the carcass 212. The cover 216 furtherincludes first and second side surfaces 238, 240, which are in contactwith the upstanding edge portions 222, 224 of the sliding layer 218,respectively.

In the example illustrated, the cover 216 includes an upper surfacehaving first and second raised portions 242, 244 and a valley 246between the first and second raised portions 242, 244. The valley 246defines a concave shape between the first and second raised portions242, 244.

In the example illustrated, the stretch inhibitor 214 is formed of aplurality of longitudinal cables 248, which are shown disposed along acentral plane within the carcass 212.

Various dimensions of the intermediate handrail product 210 areillustrated in FIG. 9. In the example illustrated, the intermediatehandrail product 210 has a product width 250, carcass width 252, avalley width 254, a raised height 256, a central height 258, an edgeheight 260, and a carcass height 274.

In the example illustrated, the first and second raised portions 242,244 are shown offset inwardly in relation to the edges 230, 232 of thecarcass 212. In other words, the valley width 254 is substantially lessthan the carcass width 252.

Dimensions for a particular example of the intermediate handrail product210 are provided in Table 9. These dimensions are intended to beillustrative but non-limiting.

TABLE 9 Dimension Reference mm product width 250 92.0 carcass width 25267.0 valley width 254 62.0 raised height 256 10.5 central height 258 8.2edge height 260 7.25 carcass height 274 6.0

As mentioned above, the handrail 10 may be manufactured generally inaccordance with the extrusion methods and apparatuses disclosed inInternational Publication No. WO/2009/033270. The intermediate handrailproduct 210 may be an extrudate product that is extruded out of a dieassembly (not shown), and requires further processing to obtain thefinal, desired profile of the handrail 10 as shown in FIG. 1.

Referring to FIG. 10, an elongate primary mandrel 262 may be used toshape the intermediate handrail product 210 into the final profile ofthe handrail 10 (FIG. 1). The mandrel 262 may include a number ofsections. In the example illustrated, the mandrel 262 has a base 264 andan upper section 266 defining a support surface. The profile of theupper section 266 changes progressively and smoothly, to form the finalhandrail profile.

In the example illustrated, extending longitudinally along the uppersection 266 is a bore 268 into which opens into slots 270. A transverseport 272 opens into the bore 268. The port 272 is connected to a vacuumsource. This maintains a vacuum within the bore 268, for example, in therange of 8 to 12 inches of mercury. The purpose of the vacuum is toensure that the sliding layer 218 closely follows the mandrel 262. Thelevel of the vacuum may be determined by that necessary to ensure goodaccurate following of the mandrel 262 profile, while at the same timenot being too high so as to create excessive drag. If a high degree ofvacuum is used, then a higher tension may have to be applied to pull thehandrail along the mandrel, and this may stretch the sliding layer 218.The exact length of the mandrel 112 will depend upon the intendedproduction rate.

As the intermediate handrail product 210 is guided along the mandrel262, outer edges of the intermediate handrail product 210 are droppeddownwardly, so as to have the effect of lessening the height of thefirst and second raised portions 242, 244 (FIG. 8). The first and secondraised portions 242, 244 provide additional material to account for thecurved shaped of the first and second side cover portions 32, 34 in thefinal profile of the handrail 10 (FIG. 1).

As the intermediate handrail product 210 is guided along the mandrel262, the upstanding edge portions 222, 224 of the sliding layer 218 maybe continuously supported along the mandrel 112 and progressivelydropped downwardly until they are generally horizontal, and thencontinued to be turned inwardly to form the final C-shaped profile ofthe handrail 10 (FIG. 1). It will be appreciated therefore that thesurfaces 238, 240 in the intermediate handrail product 210 correspond tothe surfaces 42, 44 in the handrail 10, respectively, and further thatthe surfaces 234, 236 in the intermediate handrail product 210correspond to the surfaces 46, 48 in the handrail 10, respectively.

The temperature conditions in the die assembly may be such that, onleaving the die assembly, the thermoplastic materials of theintermediate handrail product 210 are still molten. Along the mandrel262, the sliding layer 218 remains solid throughout the forming processand serves as the contact surface, and the molten thermoplasticmaterials may be untouched. The mandrel 262 may be heated or cooled inorder to maintain the intermediate handrail product 210 at an idealforming temperature. Depending on the production speeds at which theextrudate travels across the mandrel 262, cooling may in fact benecessary to maintain the mandrel at an appropriate temperature, forexample, 50° C.

At the end of the mandrel 262, the finished profile of the handrail 10may be formed, and the thermoplastic materials may still not be properlysolidified. To cool and solidify the thermoplastic materials, thehandrail 10 may be passed into a cooling unit (not shown). A pluralityof rollers (not shown) may also be implemented to cool and effect theskinning of the exterior of the handrail 10, the removal of die lines,and/or additional shaping of the exterior surface of the handrail 10.

It will be appreciated that terms used herein to convey geometrical ormathematical relationships need not be construed with absoluteprecision. For example, the terms ‘concave’ and ‘convex’ as used hereinneed not be interpreted to mean structures having a curved surface thatis exactly circular. These terms and other terms herein may beinterpreted with some flexibility, without strict adherence tomathematical definitions, as will be appreciated by persons skilled inthe art.

While the above description provides examples of one or more apparatusesor methods, it will be appreciated that other apparatuses or methods maybe within the scope of the accompanying claims.

We claim:
 1. A handrail, comprising: a carcass comprising a first sidecarcass portion, a second side carcass portion spaced apart from thefirst side carcass portion, and a central carcass portion of generallyuniform thickness extending between the first and second side carcassportions, the carcass tapering in thickness around the first and secondside carcass portions, the central carcass portion defining an upperinterior surface, and the first and second side carcass portionsdefining first and second concave interior surfaces, respectively,adjoining the upper interior surface on either side thereof; a stretchinhibitor arranged within the central carcass portion; a cover bonded tothe carcass, the cover comprising a first side cover portion coveringthe first side carcass portion, a second side cover portion covering thesecond side carcass portion, and a central cover portion of generallyuniform thickness extending between the first and second side coverportions adjacent to the central carcass portion, the central coverportion defining an upper exterior surface, the first and second sidecover portions defining first and second convex exterior surfaces,respectively, adjoining the top exterior surface on either side thereof,the first and second side cover portions further defining generallyopposed first and second side interior surfaces, respectively, and thefirst and second side cover portions yet further defining first andsecond lower interior surfaces, respectively, adjoined between the firstand second concave interior surfaces and the first and second sideinterior surfaces, respectively; and a sliding layer secured at least tothe upper interior surface and the first and second concave interiorsurfaces, wherein, at a central width axis of the handrail, a faceheight between the upper exterior surface and a bottom surface of thesliding layer is less than about 8.0 mm, wherein the carcass is formedof a first thermoplastic material, the cover is formed of a secondthermoplastic material, and the first thermoplastic material is harderthan the second thermoplastic material, and wherein the firstthermoplastic material has a modulus at 100% elongation of between 12and 15 MPa and a hardness of between 93 and 96 Shore A.
 2. The handrailof claim 1, wherein the face height is less than about 7.5 mm.
 3. Thehandrail of claim 2, wherein the face height is between 7.0 mm and 7.5mm.
 4. The handrail of claim 3, wherein, at a central height axis of thehandrail, side thickness dimensions between each of the first and secondconvex exterior surfaces and a respective inner surface of the slidinglayer is less than about 8.0 mm.
 5. The handrail of claim 4, wherein theside thickness dimension is less than about 7.5 mm.
 6. The handrail ofclaim 5, wherein the side thickness dimension is between 7.0 mm and 7.5mm.
 7. The handrail of claim 1, wherein the first thermoplastic materialhas a hardness of between 94 and 95 Shore A.
 8. The handrail of claim 1,wherein a lip stiffness force of at least 10 kg is required to increasea mouth width between the first and second side interior surfaces by 7mm in an extruded section, measured using first and second jaw elementsapplying load to the first and second side interior surfaces,respectively, of a test piece of the extruded section, each of the firstand second jaw elements extending a length of approximately 30 mm, andthe length of the test piece substantially exceeding the length of thefirst and second jaw elements.
 9. The handrail of claim 1, wherein a lipstiffness force of at least 7 kg is required to increase a mouth widthbetween the first and second side interior surfaces by 7 mm in a splicedsection, in which a joint is formed between ends of two separate lengthsof the handrail, measured using first and second jaw elements applyingload to the first and second side interior surfaces, respectively, of atest piece of the spliced section, each of the first and second jawelements extending a length of approximately 30 mm, and the length ofthe test piece substantially exceeding the length of the first andsecond jaw elements.
 10. The handrail of claim 1, wherein the firstthermoplastic material is polyester thermoplastic polyurethane having amelt flow index of between 5 and 20 g, and the second thermoplasticmaterial is polyester thermoplastic polyurethane having a melt flowindex of between 20 and 40 g.
 11. The handrail of claim 1, wherein thesliding layer comprises yarns having a residual shrinkage of at least7.0%.
 12. In combination, the handrail of claim 1 wound about a reel toform a spool of the handrail maintained in a reverse bend orientation,in which the first and second side carcass portions and the first andsecond side cover portions that are spaced from the stretch inhibitorand a neutral axis of the handrail are placed under slight tension. 13.An intermediate handrail product, comprising: a sliding layer comprisinga planar portion and first and second upstanding edge portions; acarcass on the sliding layer and centrally disposed between the firstand second upstanding edge portions, the carcass being generallyrectangular and comprising first and second edges spaced apart from thefirst and second upstanding edge portions, respectively; a stretchinhibitor arranged within the carcass; and a cover covering the carcass,and extending between the upstanding edge portions, wherein, betweeneach of the upstanding edge portions and the respective edge of thecarcass, the cover contacts the sliding layer, wherein the carcass isformed of a first thermoplastic material, and wherein the firstthermoplastic material has a modulus at 100% elongation of between 12and 15 MPa and a hardness of between 94 and 95 Shore A.
 14. Theintermediate handrail product of claim 13, wherein the cover comprises:first and second bottom surfaces that are in contact with the planarportion; first and second side surfaces that are in contact with thefirst and second upstanding edge portions, respectively; and an uppersurface having first and second raised portions and a valley between thefirst and second raised portions, and the first and second raisedportions are offset inwardly in relation to the respective first andsecond edges of the carcass.
 15. The intermediate handrail product ofclaim 14, wherein: a central height dimension between the valley and aninner surface of the sliding layer is about 8.2 mm; a raised heightdimension between the first and second raised portions and the innersurface of the sliding layer is about 10.5 mm; and a valley widthdimension between the first and second raised portions is about 62.0 mm.16. The intermediate handrail product of claim 15, wherein: a carcassheight dimension between a top surface of the carcass and an innersurface of the sliding layer is about 6.0 mm; a carcass width dimensionbetween the first and second edges of the carcass is about 67.0 mm; anda product width dimension between outer surfaces of the upstanding edgeportions is about 92.0 mm.
 17. The intermediate handrail product ofclaim 14, wherein each of the upstanding edge portions comprises acurved end that is embedded within the cover.
 18. The intermediatehandrail product of claim 13, wherein: the cover is formed of a secondthermoplastic material, and the first thermoplastic material is harderthan the second thermoplastic material; and the first thermoplasticmaterial is polyester thermoplastic polyurethane having a melt flowindex of between 5 and 20 g, and the second thermoplastic material ispolyester thermoplastic polyurethane having a melt flow index of between20 and 40 g.
 19. The intermediate handrail product of claim 13, whereinthe sliding layer comprises yarns having a residual shrinkage of atleast 7.0%.
 20. A handrail, comprising: a carcass comprising a firstside carcass portion, a second side carcass portion spaced apart fromthe first side carcass portion, and a central carcass portion extendingbetween the first and second side carcass portions, the carcass formedof a first thermoplastic material that has a modulus at 100% elongationof between 12 and 15 MPa and a hardness of between 93 and 96 Shore A; astretch inhibitor arranged within the central carcass portion; a coverbonded to the carcass, the cover comprising a first side cover portioncovering the first side carcass portion, a second side cover portioncovering the second side carcass portion, and a central cover portionextending between the first and second side cover portions adjacent tothe central carcass portion, the central cover portion defining an upperexterior surface; and a sliding layer secured to the carcass and havinga bottom surface, and, at a central width axis of the handrail, a faceheight between the upper exterior surface and the bottom surface isbetween 7.0 mm and 7.5 mm.